PROCEEDINGS OF SECTION C. 491 
come toa series of metamorphic rocks. The granite is covered 
in places by basalt, and also by drifts, but these do not concern 
us now. 
The rock on which the town is built is very much decomposed, 
and although it often appears solid, crumbles away at once before 
the hammer. Closer investigation shows that it is made up of 
coarse grains of light-grey or white felspar, much decomposed, a 
fair amount of quartz, and a little black mica (biotite). In places 
there are patches composed almost entirely of this mica, but soft 
and crumbling like the rest. It is sometimes a little difficult to 
say whether the rotten granite has decomposed zz situ, or whether 
the materials have been washed down from a higher level. In 
some cases no doubt the latter is the case, as bands of pebbles 
occur at a considerable depth from the surface. On the higher 
ground, however, the granite has no doubt decayed where we 
find it, and it is often traversed by hard veins, which are very 
distinct from the surrounding matrix. These veins appear to 
correspond very closely to some of those described by Mr. Howitt 
as occurring in the granite of Gippsland. They vary in thickness 
from less than an inch to about a foot, and may be traced some- 
times with great regularity for a considerable distance. In 
texture they vary greatly, some being excessively coarse-grained, 
the crystals of pink orthoclase and quartz being several inches in 
length. These crystals are sometimes coated with fine scales of 
white mica, while coarse plates of brown mica (muscovite) are 
also found occasionally, but are not very common. Other veins, 
however, are very fined-grained, almost micro-crystalline, and are 
a good deal like some Cornish elvans. Mr. Howitt calls his veins 
aplite, and considers they are all intrusive, I believe. Ours may 
also be intrusive, but I am yet not quite convinced that they are 
so in all cases. Some of the veins are found in the heart of the 
granite quite close to Bathurst, while others occur at the junction 
with the schists into which narrow veins sometimes penetrate, 
but for no great distance. Besides the rotten granite described 
above, we have plenty of the solid material in the neighbourhood. 
At several places near the town, hard bars of a coarse-grained 
variety of granite come to the surface, and it may also be found 
at many other places by sinking a few feet, so that it is quite 
possible that it extends under the whole area, but there have not 
been enough deep wells sunk to decide the question. The felspar 
in the hard granite is white or light grey, but sometimes is in 
large crystals of a reddish colour. The latter variety is doubtless 
orthoclase, and also much of the white, but there is likewise a 
good deal of plagioclase. I have not thoroughly analysed the 
felspars, nor am I aware that any analyses have been made. It 
would be interesting to learn their exact composition, and a more 
complete examination of their optical characters than I have been 
able to make as yet would also be interesting, as already I have 
